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I have a problem with sudo. Every time when I trying to use sudo I got this problem:
sudo: unable to resolve host ubuntu-server
My /etc/hosts file:
127.0.0.1 localhost 127.0.1.1 ubuntu-server # The following lines are desirable for IPv6 capable hosts ::1 ip6-localhost ip6-loopback fe00::0 ip6-localnet ff00::0 ip6-mcastprefix ff02::1 ip6-allnodes FF02::2 ip6-allrouters
I think there is some other setting that causes the unable to resole host, but I cannot find these.